1. Field of the Invention
The present invention relates to personal computer systems and more particularly to a method for transferring data, address and interrupt information in a split system personal computer between at least one direct access storage device in a first housing and devices in a separate processing unit via a multi-conductor electrical connector.
2. Description of Related Art
Personal computer systems are well known in the art. Personal computer systems in general, and IBM Personal Computers in particular, have attained widespread use for providing computer power to many segments of today's modern society. Personal computers can typically be defined as a desktop, floor standing, or portable microcomputer that is comprised of a system unit having a single central processing unit (CPU) and associated volatile and non-volatile memory, including all RAM and BIOS ROM, a system monitor, a keyboard, one or more flexible diskette drives, a fixed disk storage drive (also known as a "hard drive"), a so-called "mouse" pointing device, and an optional printer. One of the distinguishing characteristics of these systems is the use of a motherboard or system planar to electrically connect these components together. These systems are designed primarily to give independent computing power to a single user and are inexpensively priced for purchase by individuals or small businesses. Examples of such personal computer systems are IBM's Personal Computer AT and IBM's Aptiva.
Historically, a personal computer (PC) was a relatively large box that sat on top of a desk and contained all of the electronics--the processor, memory, IO devices, floppy disk drive, etc. This was known as the system unit and required a significant amount of desktop work space. The monitor was traditionally a cathode ray tube (CRT) that was placed on top of the system unit. The keyboard and (eventually a mouse) was placed in front of the system unit to provide for user input. Accordingly, these "desktop" computer systems combined all PC functions and accessibility in one enclosure on the desktop where significant space is required and noise sources are relatively close to the user. In addition, there was no way to compact the elements when the PC was not in use.
In order to reduce the clutter that a personal computer caused on the desktop, a tower design soon emerged that moved the system unit components into a tower form-factor that sat along-side the desk. The CRT now sat directly on the desk with the keyboard and mouse in front of it. However, this "minitower" type unit is typically placed on the floor where accessibility to drives (floppy and CD-ROM), power, and system activity (LEDs) is compromised and awkward. These two form factors (the "desktop" and "minitower" systems) have endured for quite some time with just various changes in the size, shape and color.
It is therefor desirable to provide a personal computer system form factor that significantly reduces the amount of desktop space needed, reduces noise on the desktop and provides easy accessibility to removable DASD drives. It is further desirable to provide an expansion bus interface to implement such a form factor.